Displacement diffuser with heat/cool changeover

ABSTRACT

A displacement diffuser mounted in a suspended ceiling installation for supplying both heated and cooled air and using both displacement and mixing ventilation within an occupied space from a single unit. The diffuser includes a housing, an air inlet in the housing in communication with supply air, and a dual plenum divided by an intermediate wall into a heating plenum for receiving heated air and a cooling plenum for receiving cooled air. A high velocity linear air slot diffuser in directs air from the heating plenum into an occupied space at a high velocity. A low velocity diffuser allows cooled air to move via displacement into an occupied space. A damper within the housing is capable of directing heated air into the heating plenum and cooled air into the cooling plenum in response to an actuator signal.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No.61/218,575, filed Jun. 19, 2009, which is incorporated herein byreference in its entirety.

BACKGROUND OF THE INVENTION

1. Technical Field

This invention relates to a displacement diffuser for providing bothheating and displacement cooling functions with minimal turbulence orinduction of room air from the same unit. The displacement diffuser iscapable of disbursing conditioned air using two different disbursementmethods, and is used in connection with a ducted air conditioning andheating system. The displacement diffuser provides a dual plenum with ahigh velocity linear air slot diffuser for heated air, and a lowvelocity diffuser for cooled air and is capable of both displacement andmixing ventilation. The system switches from cooling to heating mode viaan electronic actuator or a signal activated by duct temperature fromthe HVAC system.

2. Prior Art

Airflow in ventilated spaces generally can be classified into twocategories: mixing (or dilution) ventilation and displacementventilation. Mixing ventilation systems generally supply air in a mannersuch that the air in an entire room is fully mixed. The conditionedsupply air exits the outlet at a high velocity, inducing room air toprovide mixing and temperature equalization. Ideally, when the air in anentire room is fully mixed, temperature variations throughout the spaceare small while the contaminant concentration is uniform throughout thezone.

Mixing ventilation typically uses a high outlet velocity to mix thesupply air with the ambient air at the ceiling level. The air thatreaches the occupied zone is, then, a mixture of supply and ambient air.This system can be contrasted with a displacement ventilation system,where cool supply air is typically distributed with a low velocity tothe floor level of a ventilated space, which results in the supply airreaching the occupied zone without any significant mixing of cool andcontaminated ambient air. Thus, in mixing ventilation, the situation isopposite. Mixing systems successfully achieve changes in overall roomtemperature by thoroughly mixing conditioned supply air with ambient orroom air. Impurities and heat within an occupied space are diluted andmixed.

The supply air in a mixing system is used to dilute the concentration ofcontaminants in the room (this is why it is also called dilutionventilation) but not to displace them. Unless the sources ofcontamination are evenly distributed throughout the space, however, highconcentration levels of contaminants are always found near thesesources. Because the conditioned air is usually supplied at a high level(above the occupied zone), the concentration levels above the occupiedzone are generally lower than those existing within the zone, whichresults in a lower overall relative ventilation efficiency. In addition,stagnant zones of high concentration levels and/or short circuiting ofconditioned air to extract points can cause a sharp drop in theventilation efficiency.

A displacement ventilation system introduces air into an occupied spaceat low velocities, which causes minimal induction and mixing.Displacement outlets have been traditionally located at or near floorlevel. The system utilizes buoyancy forces generated by heat sourcessuch as people, lighting, computers, and electrical equipment in a roomto remove contaminants and heat from the occupied zone.

Conventional displacement ventilation systems generally supply cool airalong the floor in a thin layer less than about a foot in height. Thesupply air spreads across the floor in a manner similar to water flowingout of a tap, filling the entire space. If obstructions such asfurniture or partitions are encountered, the air will flow around andbeyond the obstruction. When cool air meets a heat source such as aperson or a piece of equipment, a portion of the conditioned air iscaptured by the thermal plume of the heat source, while the remainder ofair continues further into the room. In a displacement ventilationsystem, fresh air pools at floor level and personal thermal plumes drawfresh air up the body while polluted air is extracted at thehigh-mounted return.

Displacement ventilation is often used to compensate for changing loadscontained within an occupied space. Additionally, displacementventilation outlets may have a lower pressure drop which could allow fora reduction in fan energy with the selection of smaller fan components.The superior air quality and low noise levels make displacementventilation better suited for offices, classrooms, theaters, hotels orany application where air quality demands are high.

Displacement ventilation relies on the principle that thermal plumesdrive the movement of the air within the space. Supplying a space withhot air at the same flow velocities required by displacement ventilationis not generally recommended because the supply air does not have enoughforward momentum to overcome the effects of buoyancy, and will rise tothe ceiling level and be exhausted or returned, bypassing the occupiedzone.

Although displacement ventilation systems seem to be, in principle, moreeffective at meeting ventilation needs than the equivalent mixingapproach, air cooling or heating capacity is limited by nature of theneed for careful thermal control of the supply air temperature.Supplemental air conditioning must usually be employed through anadditional system, such as through radiating ceiling panels. Further,unlike mixing ventilation, the spatial concentration of pollutant withinan occupied space is non-uniform, with air upstream of the pollutantsource being uncontaminated while the air downstream of source may beheavily contaminated. Displacement ventilation alone also can produce ahigh concentration level of airborne contaminants. In some situations,mixing ventilation is considerably more robust compared withdisplacement ventilation, while in other situations, displacementventilation can be more effective than mixing ventilation when movementsprevail, even though the movements reduce the effectiveness of theoverall system.

Additionally, because conventional displacement ventilation systems aregravity driven, caution must be used in sloped applications. A theaterwith even seating will require less diffusers in the lower sections ofthe theater and more in the upper to compensate the natural movement ofair to the lower portion of the theater. Also, displacement systemsrequire a return located as high as possible within the space to removeas much of the polluted/hot air as possible, ideally at ceiling height.If the return air is located below the ceiling, the air above the returnmay not be exhausted properly from the space and polluted or hot air mayremain in the occupied zone. Thus, conventional diffuser systems take upconsiderable space both at the floor level, where the supply air entersthe room, and at the ceiling level for the return air.

Conventional dual heating and cooling displacement diffusers incorporatea concentrically-oriented, radial displacement outlet with an outer ringand central core with jet diffusers. A damper connected to the centraltube closes in cooling mode, forcing cooled air vertically into anoccupied space from the outer ring, which descends downward into theroom at a low velocity. The damper is open in heating mode and asupporting jet directs heated air down the core and out of the diffuserat a higher velocity. This type of conventional heating/coolingdisplacement diffuser does not completely shut off the supply air to thelow velocity, outer ring regardless of the position of the damper.Therefore, conditioned air exiting the diffuser face will be inducedinto the air from the high velocity supporting jet of the central core.This creates a buffer zone between the supporting jet and the ambientroom air, virtually eliminating any mixing of the conditioned andambient air. In operation, this type of conventional heating/coolingdiffuser will adjust the momentum given to the conditioned air based onthe differential between the conditioned and ambient room airtemperatures.

While this typical system has a mechanism for changing the momentum ofthe discharge air from low in cooling mode to high in heating mode, itlacks the ability to change the air distribution method fromdisplacement ventilation. Although using a displacement ventilationmethod for both heating and cooling may be ideal for removing pollutantsfrom the environment in industrial applications, the relativeinflexibility of the conventional “displacement-only” heating/coolingsystem makes it inappropriate for use outside of industrial spaces. Thevelocity and air pattern caused by the supporting jet make it unsuitablefor use in areas where thermal comfort is a priority, like offices,theaters and the like.

Accordingly, there is a need for a device that allows for the heatingand cooling of a variety of configurations of an occupied space havingvarious contaminant loads and rates of movement within the space wherethermal comfort of occupants is a priority. There is a need for a mixingdiffuser capable of changing its air circulation method to maximizecomfort in both a heating and a cooling mode. There is additionally aneed for a device that ensures a comfortable environment for buildingoccupants who are highly sensitive to vertical air movement (drafts)that may pass over their body from overhead high velocity airstreams.There is also a need for such a device that is compact, easy to installand operate, and compatible with both heating and cooling functions fromthe same unit. There is a further need for a single device thatovercomes the challenges of flow velocities needed when supplying aspace with hot air such that the supply air has enough forward momentumto overcome the effects of buoyancy while providing a comfortableenvironment. Finally, there is a need for such a device that consumesminimal usable space within a room. It is to these needs and others thatthe present invention is directed.

BRIEF SUMMARY OF THE INVENTION

The displacement diffuser of the present invention is constructed of twoseparate sections within the internal plenum: one for a heatingoperation, and one for a cooling operation. The housing of thedisplacement diffuser has one air inlet in communication with supplyair. The heating plenum has a high velocity linear air slot diffuser,while the cooling plenum has a low velocity diffuser. A pivoting damperdirects heated air into the heating plenum for high-velocity mixingventilation, and cooled air into the cooling plenum for low velocitydisplacement ventilation.

The displacement diffuser produces a one-way low velocity air supplyfrom a suspended ceiling installation. It discharges air evenly acrossthe perforated face with minimal turbulence or induction of room air.The cool supply air flows from the ceiling, through the low velocity airoutlet, and down to the floor level to gradually fill the space. It canbe installed in a standard suspended ceiling, freeing up valuable floorspace, and reducing needed ducting.

The displacement diffuser of the present invention offers a heating modewhich, when supplied with warm air, will force supply air down into theoccupied space. The device according to the present invention operatesin both a heating and cooling mode, both utilizing the same air inlet,by varying the velocity of the conditioned air being supplied to thespace according to whether the device is utilizing the heating orcooling function. The velocity of the air is controlled through the dualfaces of the displacement diffuser of the present invention: a highvelocity linear air slot diffuser and a low velocity diffuser. Thisallows cool, slow moving air to travel through one section from asectioned portion of the dual plenum and warm, fast moving air throughanother sectioned portion of the dual plenum in order to provide alocalized mixed zone of warm air near the diffuser. Cooled, low velocityair circulates in the room through displacement ventilation, but changesto mixing ventilation when the displacement diffuser is switched to ahigh velocity heating mode. This ability to switch from displacementventilation to mixing ventilation maximizes the comfort of individualsin the room by eliminating drafts.

Conditioned air is supplied to the displacement diffuser of the presentinvention via a ducted connection. The dual plenum is tightly sealed toensure optimum operation in a pressurized environment. Theceiling-mounted location of the device allows for both efficient andeffective mixing and induction ventilation, while freeing up valuablefloor space needed for conventional systems.

A pivoting dual blade damper within the diffuser can be rotated todirect either heated air into a heating section of the plenum (theheating plenum), or cooled air into a cooling section of the plenum (thecooling plenum). The damper can pivot in reaction to the temperature ofthe air through a signal from the HVAC system or in response to anelectric or thermally powered actuator.

The cooling plenum is constructed with an equalization baffle behind theoperative perforated diffuser face for uniform, low velocitydistribution of supply air. Both the equalization baffle and theperforated diffuser face are securely fastened to the diffuser frame ofthe housing. The diffuser frame ensures the rigidity and positioning ofthe equalization baffle. The heating plenum has a linear air slotdiffuser which can be constructed of heavy wall extruded aluminum airdeflector frames.

Steel air pattern controllers are fully adjustable to allow movementfrom side to side to create various air pattern configurations. Thediffuser utilizes a modulating actuator controlling the dual bladedamper allowing two separate air flow paths. The actuator closes theheating plenum when in cooling mode, and closes the cooling plenum whenin heating mode.

One feature of the present invention is a simple device that allows forthe heating and cooling of a variety of configurations of an occupiedspace having various contaminant loads and rates of movement within thespace. Another feature of the present invention is that it is compact,easy to install and operate, and compatible with both heating andcooling functions in the same unit. Another feature of the presentinvention is that the displacement diffuser is capable of changing itsair circulation method from displacement ventilation to mixingventilation to maximize comfort in both a heating and a cooling mode.Yet another feature of the present invention is that it ensures acomfortable environment for building occupants who are highly sensitiveto drafts that may pass over their body from overhead high velocityairstreams. Yet another feature of the present invention is a singledevice that overcomes the challenges of flow velocities needed whensupplying a space with hot air such that the supply air has enoughforward momentum to overcome the effects of buoyancy while providing acomfortable environment. Yet another feature of the present invention isa ventilation device that consumes minimal usable floor space within aroom. Still another feature of the present invention is a ventilationdevice having a dual plenum that fits easily into a ceiling grid yet isadaptable for mounting in unique mounting spaces.

These features, and other features and advantages of the presentinvention will become more apparent to those of ordinary skill in therelevant art when the following detailed description of the preferredembodiments is read in conjunction with the appended drawings in whichlike reference numerals represent like components throughout the severalviews.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 cross-sectional side view of a displacement diffuser with aheating and cooling function in accordance with the present invention.

FIG. 2 is a side elevation view of a displacement diffuser with aheating and cooling function in accordance with the present invention.

FIGS. 3 and 4 are corner perspective views of the bottom and sides oftwo embodiments of a displacement diffuser with a heating and coolingfunction in accordance with the present invention.

FIG. 5 is a side view of a displacement diffuser with a heating andcooling function in accordance with the present invention.

FIG. 6 is a bottom plan view of a displacement diffuser with a heatingand cooling function in accordance with the present invention.

FIG. 7 is a corner perspective view of the top and front of analternative embodiment of a displacement diffuser in accordance with thepresent invention.

FIG. 8 is a corner perspective view of the top and front of anotheralternative embodiment of a displacement diffuser in accordance with thepresent invention.

FIG. 9 is a corner perspective view of the top and front of yet anotheralternative embodiment of a displacement diffuser in accordance with thepresent invention.

FIG. 10 is a bottom view of the alternative embodiment of the presentinvention shown in FIG. 9.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Illustrative embodiments of a device according to the present inventionare shown in FIGS. 1 through 6. FIG. 1 cross-sectional side view of anembodiment of the displacement diffuser with a heating and coolingfunction in accordance with the present invention. FIG. 2 is a sideelevation view of an embodiments of the displacement diffuser with aheating and cooling function in accordance with the present inventionshowing the exterior of the diffuser of FIG. 1, and detailing thecontrol mechanism. FIGS. 3 and 4 are corner perspective views of thebottom and sides of two embodiments in different dimensions of adisplacement diffuser with a heating and cooling function in accordancewith the present invention in which an internal gasket can be seen inthe duct housing. FIG. 5 is a side view of an embodiment of thedisplacement diffuser with a heating and cooling function in accordancewith the present invention from an end of the diffuser containing theduct housing, the pivoting damper blades, a gasket, and the actuator.FIG. 6 is a bottom view of an embodiment of the displacement diffuserwith a heating and cooling function in accordance with the presentinvention showing the perforated diffuser face.

FIG. 7 is a corner perspective view of the top and front of analternative embodiment of a displacement diffuser in accordance with thepresent invention. The unit has a triangular profile such that it can bemounted in a corner of a room. A linear grille section can be seen atthe bottom of this exemplary embodiment, which serves as theheating/mixing outlet. Also, a perforated low velocity diffuser is seenextending to the top of this exemplary embodiment, which serves as thedisplacement ventilation section. Similarly, FIG. 8 is a cornerperspective view of the top and front of another alternative embodimentof a displacement diffuser in accordance with the present invention.This unit has a semi-circular profile. FIG. 9 is a corner perspectiveview of the top and front of yet another alternative embodiment of adisplacement diffuser in accordance with the present invention. Thisunit has a pie-shaped profile which is also particularly suitable forcorner mounts. FIG. 10 shows the bottom profile of the pie-shaped unitshown in FIG. 9.

The present invention is an economical and space-saving diffuser thatprovides both a mixed ventilation heating system and a displacementventilation cooling system in one unit.

The present invention is suitable for indoor living spaces in which themaximum utilization of floor space is desirable. The displacementdiffuser is intended for mounting in a suspended ceiling installationfor applications requiring both cooling and heating. The diffuser isdesigned to produce a vertical low velocity displacement air patternwhen supplying cool air or a horizontal high velocity pattern whensupplying heated air. The diffuser switches from cooling to heating modeor vice versa with an electric or thermally powered actuator activatedby a signal from the HVAC system or by duct temperature. When thedisplacement diffuser is in cooling mode it discharges air evenly acrossthe perforated face with minimal turbulence or induction of room air.The cool air falls slowly to the floor and gradually fills the space.When the displacement diffuser is in heating mode, it discharges airparallel or normal to the perforated diffuser face toward the perimeterof an occupied space with a high velocity jet.

With reference to FIG. 1, an illustrative example of a displacementdiffuser 10 according to the present invention comprises a housing 12containing a dual plenum 14 which facilitates heating/coolingchangeover. The dual plenum 14 is separated into two parts by anintermediate wall 16. The first part of the dual plenum 14 created bythe intermediate wall 16 comprises a heating plenum 18, and the secondpart of the dual plenum 14 created by the intermediate wall 16 comprisesa cooling plenum 20. The displacement diffuser 10 also comprises asingle air inlet (the combination of 22 and 28), which is partitioned onone side to serve as a heated air inlet 22 when in heating mode, andpartitioned on the other side to serve as a cooled air inlet 28 when incooling mode so that heating and cooling modes do not operatesimultaneously.

The heating plenum 18 receives heated air through the heated air inlet22 from the duct via the duct housing 24 and releases the heated airinto an occupied space via a high velocity linear air slot diffuser 26.Similarly, the cooling plenum 20 receives cooled air through the cooledair inlet 28 from the duct which is connected to the diffuser via theduct housing 24 and releases the cooled air into an occupied space via alow velocity diffuser 30. Air pattern controllers 32 located within thecooling plenum 20 adjacent the low velocity diffuser 30 are mounted to apivot 34 at each end so that they are fully adjustable to allow movementof cooled air from side to side to create various air patternconfigurations and are fully adjustable to allow shut-off without addingany blank-off devices.

Heating and cooling changeover is accomplished by an actuator 36 mountedon the duct housing 24 which controls a dual-blade damper 38 a and 38 ballowing two separate air flow paths. The blades of the dual-bladedamper 38 a and 38 b connect at one end and form an angle such that agasket 40 attached to the other end contacts a side of the duct housing24 and the intermediate wall 16. The actuator 36 closes the heatingplenum 18 when in cooling mode, and closes the cooling plenum 20 when inheating mode. The actuator 36 remains accessible from the outside of thedisplacement diffuser 10 for servicing. For example, a gasket 40 of oneblade of the dual-blade damper 38 a may contact a side of the ducthousing 24 and another gasket 40 of the second blade of the dual-bladedamper 38 b may contact the intermediate wall 16 when the actuator 36signals for cooling mode. Because the heating plenum 18 is closed off bythe dual-blade damper 38 a and 38 b, cooled air is directed through thecooling plenum 20. The actuator 36 can be, for example, a 24 VACmodulating actuator, a floating point modulator, a thermal wax actuator,or any appropriate actuating system known in the art.

An embodiment of the displacement diffuser 10 of the present inventionhas a dual plenum 14, one section for heating operation, the heatingplenum 18, and one section for cooling operation, the cooling plenum 20.The cooling plenum 20 is constructed with an equalization baffle (notshown) behind an operative diffuser face 44 (as displayed in FIG. 6) foruniform, low velocity, distribution of supply air. Both the equalizationbaffle and the perforated diffuser face 44 are securely retained to adiffuser frame 46.

In one embodiment, the diffuser frame 46 is constructed of steel and iswelded to ensure rigidity and positioning of the equalization baffle.Another embodiment has no visible fasteners on the perforated diffuserface 44. The perforated diffuser face 44 can additionally be constructedof painted high-gauge steel, while the dual plenum 14 is constructed ofsatin coat steel, and the equalization baffle is preferably constructedof aluminum. In another exemplary embodiment, the high velocity linearair slot diffuser 26 for the heating plenum 18 is constructed of heavywall extruded aluminum air deflector frames.

Referring now to FIG. 2, a side view of an embodiment of thedisplacement diffuser 10 of the present invention comprises a housing 12and a diffuser frame 46 connected to the bottom of the housing 12. Theactuator 36 is seen in more detail connected to the side of the ducthousing 24.

Referring now to FIGS. 3 and 4, two embodiments of the displacementdiffuser 10 of the present invention are shown, with the sides of thehousing 12, the duct housing 24, and the perforated diffuser face 44clearly visible in relation to one another. The perforated diffuser face44 is connected to and surrounded by the diffuser frame 46. The highvelocity linear air slot diffuser 26 is located adjacent the perforateddiffuser face 44 and opposite the duct housing 24. Cooled air istransmitted into an occupied space through the perforated diffuser face44, and alternatively, heated air can be transmitted into an occupiedspace through the high velocity linear air slot diffuser 26. The linearair slot diffuser 26 is constructed to direct the air horizontally,normally, or in the direction of a contaminant.

The conditioned air travels from a duct (not shown) into the dual plenum14 by first entering the duct housing 24, which connects thedisplacement diffuser 10 to the duct. The actuator 36 can be, forexample, a thermal wax actuator or an electronic actuator, and isactivated electronically or by a duct temperature signal from the HVACsystem, and directs either heated air into the heating plenum 18 orcooled air into the cooling plenum 20. As heated or cooled air entersthe duct housing 24 from the duct, a gasket 40 attached to the ducthousing 24 or to the dual blade damper 38 a and 38 b (FIG. 1) provides aseal to prevent leakage of air from one plenum to another within thedual plenum 14.

Referring now to FIG. 5, an embodiment of the displacement diffuser 10of the present invention shown from the side at the connection point tothe duct housing 24 comprises the duct housing 24 attached to the sideof the housing 12. The dual blade damper 38 a is shown engaged in aheating mode. The blade face of dual blade damper 38 a is seencontacting the top of the duct housing 24 and is pivoted to a verticalposition on pivot 34 while dual blade damper 38 b (not shown) is in ahorizontal position. The individual blades of the dual blade damper 38 aand 38 b form an angle such that each contacts either the duct housing24 or the intermediate wall 16 at the gasket 40. The gasket 40 attachedeither to the dual blade damper 38 a and 38 b or the duct housing 24prevents air leakage. In one embodiment, the individual blades of thedual blade damper 38 a and 38 b are between 45 and 180 degrees relativeto each other. In another embodiment, the individual blades of the dualblade damper 38 a and 38 b are approximately 90 degrees relative to eachother. A rotating mechanism of the actuator 36, when engaged, turns thepivot 34 to rotate the dual blade damper 38 a and 38 b to engage heatingor cooling mode.

Referring now to FIG. 6, an embodiment of the displacement diffuser 10of the present invention shown from the bottom comprises a perforateddiffuser face 44 mounted to a diffuser frame 46. The perforated diffuserface 44 corresponds to the cooling plenum 20 and is adjacent to the lowvelocity diffuser 30 for the induction of cooled air into an occupiedspace to accomplish displacement ventilation. The high velocity linearair slot diffuser 26 is adjacent to the perforated diffuser face 44 andto the heating plenum 18, which directs and mixes heated air withambient room air at a high velocity into an occupied space to accomplishmixing ventilation. In one embodiment, the heated air is directed by theair slot diffuser 26 along the ceiling of an occupied space for optimalmixing of the heated air. In other embodiments, the heated air isdirected by the air slot diffuser 26 toward problem areas or largeobstacles within an occupied space, as desired by an occupant or foroptimal mixing of the heated air. The diffuser frame 46 is mounted onthe housing 12, and the housing 12 is mounted on the duct housing 24.Mounted to the duct housing 24 is the actuator 36.

In another embodiment, an equalization baffle (not shown) is positionedbehind the perforated diffuser face 44 and within the housing 12 betweenthe cooled air inlet 28 and the low velocity diffuser 30. Theequalization baffle is a flat, perforated plate with a plurality ofevenly spaced holes that accommodates the equal distribution ofconditioned air and air pressure across the low velocity diffuser 30.The equalization baffle 42 equalizes the pressure across the lowvelocity diffuser 30, thereby ensuring a consistent and perpendicularflow of air to the low velocity diffuser 30. In another embodiment, anequalization baffle 42 is within the housing 12 between the heated airinlet 22 and the high velocity linear air slot diffuser 26. Theequalization baffle 42 can be constructed from any suitable materialknown in the art, namely aluminum. The perforated diffuser face 44,diffuser frame 46, and dual plenum 14 likewise can be made from anysuitable material, preferably coated steel. The displacement diffuser 10can also utilize a 24 VAC floating point actuator 36. In a preferredembodiment, the overall plenum height of both the heating plenum 18 andthe cooling plenum 20 is less than 12 inches in order to facilitate easeof installation into a standard ceiling without compromising throwcapability of the heating function. In another preferred embodiment, theoverall height of both the heating plenum 18 and cooling plenum 20 is 8inches. The single air inlet (the combination of 22 and 28) supportingboth heating and cooling modes in a single device further contributes tothe displacement diffuser's advantageous space saving and qualities andease of installation.

Various embodiments of a displacement diffuser 10 in accordance with thepresent invention include different shapes. For example, as seen in FIG.7, the displacement diffuser 10 can be formed generally in the shape ofa triangular prism. The unit can be mounted in a corner such that thediffuser face 44 and the linear air slot diffuser 26 face outward fromthe mount and direct air into an occupied space. Similarly, thedisplacement diffuser 10 can be mounted in any suitable complimentarysetting, or can serve as a stand-alone or suspended unit within a room.The duct housing 24 can be connected to a duct either inside of a wallor ceiling or outside of a wall or ceiling if the duct is exposed withthe occupied space. The generally triangular profile of this embodimentcan also incorporate rounded “corners,” or a trapezoidal shape, whereone or more “corners” of the displacement diffuser housing 12 isflattened.

In other embodiments of the displacement diffuser 10 a generallysemi-circular profile is incorporated, with the unit generally in theshape of a semi-circular prism, as seen in FIG. 8; or a generallypie-shaped profile, as seen in FIGS. 9-10, is used. Again, these unitscan mount against or partially within a wall or ceiling, or in a corner,such that the diffuser face 44 and linear air slot diffuser 26 faceoutward and direct air into an occupied space. Alternatively, theseunits can serve as free-standing or suspended units. Other suitableshapes can also be used in conjunction with the present invention,including an arc-shaped device (not shown) or any shape known in the artto be capable of housing a dual plenum 14 connected to a diffuser face44, a linear air slot diffuser 26, and a duct housing 24.

The displacement diffuser 10 according to one embodiment is designed tobe installed in a standard suspended ceiling, freeing up valuable floorspace and reducing ducting. To handle skin loads, the displacementdiffuser 10 may be installed adjacent to the building perimeter. Thesuperior air quality and low noise levels make the present inventionsuitable for offices, classrooms or any application where air qualitydemands are high, where floor space is minimal, and where there is arequirement for both cooling and overhead heating.

While this invention has been described with reference to preferredembodiments thereof, it is to be understood that variations andmodifications can be affected within the spirit and scope of theinvention as described herein and as described in the appended claims.

1. A displacement diffuser for supplying both heated and cooled air toan occupied space, comprising: a. a housing; b. a single air inlet insaid housing in communication with supply air; c. a dual plenumcomprising a heating plenum for receiving heated air and a coolingplenum for receiving cooled air; d. a high velocity linear air diffuserin communication with the heating plenum; e. a low velocity diffuser incommunication with the cooling plenum; and f. a damper capable ofdirecting heated air into the heating plenum and cooled air into thecooling plenum.
 2. The displacement diffuser of claim 1, wherein thedamper comprises at least two blades.
 3. The displacement diffuser ofclaim 1, wherein the damper further comprises a gasket.
 4. Thedisplacement diffuser of claim 1, further comprising a duct housingattached to said housing for connecting said displacement diffuser witha duct.
 5. The displacement diffuser of claim 1, further comprising anair pattern controller at said low velocity diffuser.
 6. Thedisplacement diffuser of claim 1, further comprising an equalizationbaffle within said housing between said air inlet and said low velocityair diffuser.
 7. The displacement diffuser of claim 1, furthercomprising a diffuser frame attached to said housing adjacent to the lowvelocity diffuser and a perforated diffuser face attached to saiddiffuser frame.
 8. The displacement diffuser of claim 2 furthercomprising a pivot, wherein an edge of each of the blades is attached tosaid pivot.
 9. The displacement diffuser of claim 2, wherein the damperfurther comprises a gasket.
 10. The displacement diffuser of claim 2,further comprising two gaskets mounted to said housing, wherein onegasket is in communication with one blade of the damper when the damperis engaged in a heating mode, and wherein other gasket is incommunication the other blade of the damper when engaged in a coolingmode.
 11. The displacement diffuser of claim 4, further comprising anactuator connected to said duct housing, wherein said actuator rotatesthe dual-blade damper to direct heated air into the heated air plenumand cooled air into the cooled air plenum.
 12. A displacement diffuserfor supplying both heated and cooled air from a single unit to anoccupied space, comprising: a. a housing; b. a single air inlet in saidhousing communication with supply air; c. a dual plenum comprising aheating plenum for receiving only heated air and a cooling plenum forreceiving only cooled air separated by an intermediate wall within saiddual plenum; d. a high velocity linear air diffuser in communicationwith the heating plenum; e. a low velocity diffuser in communicationwith the cooling plenum; f. a damper within the air inlet capable ofdirecting heated air into the heating plenum and cooled air into thecooling plenum; and g. an actuator capable of moving said damper inresponse to a signal.
 13. The displacement diffuser of claim 12, whereinthe damper comprises at least two blades.
 14. The displacement diffuserof claim 12, wherein the damper further comprises a gasket.
 15. Thedisplacement diffuser of claim 12, further comprising an air patterncontroller at said low velocity diffuser.
 16. The displacement diffuserof claim 12, further comprising an equalization baffle within saidhousing between said cooled air inlet and said low velocity airdiffuser.
 17. The displacement diffuser of claim 12, further comprisinga diffuser frame attached to said housing adjacent to the low velocitydiffuser and a perforated diffuser face attached to said diffuser frame.18. The displacement diffuser of claim 13 further comprising a pivot,wherein an edge of each of the blades is attached to said pivot.
 19. Thedisplacement diffuser of claim 13, further comprising two gasketsmounted to said housing, wherein one gasket is in communication with oneblade of the damper when the damper is engaged in a heating mode, andwherein other gasket is in communication the other blade of the damperwhen engaged in a cooling mode.
 20. A displacement diffuser forsupplying both heated and cooled air from a single unit to an occupiedspace, comprising: a. a housing; b. a duct housing connected to saidhousing for further connecting said housing to a duct; c. a dual plenumcomprising a heating plenum for receiving heated air and a coolingplenum for receiving cooled air separated by an intermediate wall withinsaid dual plenum; d. a single air inlet capable of being partitionedinto:
 1. a heated air inlet in said housing in communication with heatedsupply air and said heating plenum; and a cooled air inlet in saidhousing in communication with cooled supply air and said cooling plenum;e. a high velocity linear air diffuser in communication with the heatingplenum, wherein said linear air slot diffuser directs heated air in ahorizontal direction or toward a wall within an occupied space andutilizes mixing ventilation; f. a low velocity diffuser in communicationwith the cooling plenum, wherein said low velocity diffuser utilizesdisplacement ventilation; and g. a damper in communication with saidduct housing and said intermediate wall capable of directing heated airinto the heating plenum and cooled air into the cooling plenum.